i used a coke bottle as the chamber. it runs on hairspray and a standard sparker. the barrel unscrews to fuel and a 6mm airsoft bb can be breach loaded. i put a small notch in the barrel right in the breach so the bb will stay put. you can see a large blue flash when it fires but it doesnt fire reliably even when i use the same amount of fuel. it is so light that it has the same kick as a .22lr pistol

dude. your going way overkill on your chamber. a longer barrel would certainly help performance, not a bad first guy though. if you want to fix the reliability issue, try using your breath or a small fan to vent the chamber out between shots.

the reason it kicks so much is that it is so light. the heaviest part is the 1 1/2 in pvc grip. i plan to switch to propane but i am still new to spudguns. this time last year the best i had was a 1 1/2 in tank and a 1/2 in ball valve. the bbs that i am using are .12g because thats all i have

rcman50166 wrote:maybe not as much as a .22 pistol. Using the law of conservation of energy it would be calculated the the muzzle velocity of the bb (@ .25g) must be 3045 ft/s

but wouldn't that only be true if you assumed that the mass of the .22 weapon was the same as the mass of the airsoft gun?

No the mass of the weapon itself determines how the kick feels, whether it accelerates or jerks. However the power of the kick is all determinant on the time it takes to recoil. Either way the same amount of energy is being absorbed.

That and In my experience, the kick felt with small-bore combustion like that is due to the constriction of the barrel. You will find that the kick is the same with and without the BB loaded, and if you had some way of doing High speed photography, You'd be able to see that the kick your getting is being achieved FAR after the BB has left.

thanks. my friend is getting me the stuff to run this off butane. i have some i use to refill lighters. what is stronger butane or propane? also the kick is fun. i tested this outside today. i shot a .12 bb at a shotgun clay point blank and it punched out the center. the only guns i have that can do that are over 350fps. when i shoot it i can see that it is faster than my 350fps pistol but not faster than my 430fps rifle. of 2 shots i saw 1 was about 350 and the other was about 380. i cant wait to get this running on butane

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